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皱纹盘鲍脓疱病的组织学和超微结构研究 总被引:19,自引:0,他引:19
1993年9月以来,大连地区许多养鲍厂的皱纹盘鲍都发生了严重的脓疱病。通过病理组织切片研究证明,脓疱病的病灶是从鲍足下表面开始逐渐扩展向足的深部,由于该病的唯一病原菌-河流弧菌Ⅱ的大量繁殖瞳的结缔组织、肌纤维坏死瓦解或破碎,病灶中只剩下鲍的血淋巴细胞、弧菌及细胞碎片。 相似文献
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河流弧菌—Ⅱ(Vibrio fluvialis—Ⅱ)噬菌体—VP8的分离与研究 总被引:4,自引:0,他引:4
1996年夏季,从皱纹盘鲍脓疱病发病区采集海水样品46份,以皱纹盘鲍脓疱病病原菌河流弧菌-Ⅱ(Vibriofluvialis-Ⅱ)为指示菌,从这些样品中分离纯化到多株噬菌体,并对其中VP8进行了电子显微镜观察及生物学特性研究。其头部20面体的直径约57nm;尾鞘宽为18nm,长的33nm;尾轴宽约7nm,长约58nm;从形态上看属于BradlcyA型。 相似文献
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皱纹盘鲍一种球形病毒的感染及其发生 总被引:9,自引:0,他引:9
在发病的皱纹盘鲍(HaliotisdiscushannaiIno)幼鲍的足、内脏团、外套膜的血细胞质内,发现一种直径为90~140um的球形病毒粒子,带双层囊膜,无包涵体。负染病毒粒子与超薄切片大小形态相同。用被病毒感染的患病幼鲍感染健康鲍获同样症状,死亡率为50%。并于人工感染死亡鲍鱼体内观察到同样病毒。 相似文献
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鲍鱼酶的制备及其性质 总被引:1,自引:0,他引:1
为了开发对海带(Laminaria japanic)具有解壁或破壁作用的工具酶,从皱纹盘鲍(Haliotis discus hannai Ino)的消化腺提取制备了鲍鱼酶干粉。本文报道鲍鱼酶的制备及其主要性质,并与贻贝酶进行了比较。 相似文献
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为研究对二甲苯对皱纹盘鲍肝胰腺的毒性作用,设置4个浓度(0.5、1.0、1.5和2.0 mg·L-1)和对照组,开展为期21 d的对二甲苯对皱纹盘鲍的亚慢性毒性试验,采用彗星试验技术进行皱纹盘鲍肝胰腺细胞DNA损伤分析,采用CASP分析软件对拖尾率、彗星尾长、彗尾DNA相对含量、Olive矩等损伤指标进行统计。结果表明: 与对照组相比,各染毒组皱纹盘鲍肝胰腺细胞DNA均受到损伤,且损伤程度存在显著性差异。随着染毒浓度的增加,肝胰腺细胞DNA受损程度加重,高浓度甚至可以引发细胞凋亡,呈现一定的剂量-损伤效应。中浓度对二甲苯短时间暴露即可对皱纹盘鲍肝胰腺细胞造成DNA损伤,随着暴露时间延长,细胞DNA受损程度加重,呈现一定的时间-损伤效应。但长时间暴露细胞DNA各损伤指标有所减小,这可能与细胞自身的DNA修复机制和生物体解毒系统的代谢机制有关。研究表明,对二甲苯可对皱纹盘鲍肝胰腺细胞产生氧化损伤,导致DNA断裂,高浓度的对二甲苯长时间暴露可导致其细胞凋亡。 相似文献
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皱纹盘鲍稚鲍剥离后大量死亡的原因和防治方法初探 总被引:1,自引:0,他引:1
本文报告了对大连地区皱纹盘鲍(H.discus)人工育苗过程中,稚鲍剥离后大量死亡现象的初步研究工作。实验表明,稚鲍赖以生存的波纹板上饵料残渣的积累和腐败,微生物的大量繁殖,粘液状物质的形成与稚鲍的死亡密切相关。实验中从病鲍个体及粘液状中分离出了十株优势菌,筛选出了四种有效的杀菌药物,并测出了每种药物的MIC值,实验结果在生产实际中应用取得了良好的效果。 相似文献
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在以酪蛋白和明胶为蛋白源的半精制基础饲料中,添加不同浓度梯度的钾(0、2、4、8、16、32 g钾/kg饲料),钾源为KCl,配制成6种实验饲料(实测钾含量分别为:0.10、2.12、4.39、9.79、20.08和27.26 g/kg),探讨皱纹盘鲍(Haliotis discus hannai)幼鲍对饲料中钾的需求量及其在长期适应不同含量钾的过程中的生理反应。幼鲍初始体重为(0.24±0.00)g,初始壳长为(12.24±0.04)mm,实验在流水系统中进行,养殖周期为15周。实验期间水温12—23℃,海水钾含量为(472.94±3.59)mg/L。结果表明,饲料中不同含量的钾对皱纹盘鲍的增重率(WGR,%)、贝壳日增长(DISL,μm/d)及存活率没有显著影响(P>0.05)。皱纹盘鲍软体部的水分、粗脂肪和贝壳的灰分含量受饲料中钾含量的影响不显著(P>0.05)。当饲料中钾含量大于等于4.39 g/kg时,与0.10 g/kg饲料组相比,软体部粗蛋白质含量显著升高(P<0.05)。软体部钾的含量和贝壳中钾、钠的含量受饲料中钾含量的影响不显著(P>0.05)。幼鲍软体部钠含量在饲料钾含量为20.08、27.26 g/kg时显著低于其他各组(P<0.05)。鳃Na+-K+ATP酶活力随着饲料中钾含量的增加逐渐下降,当饲料中钾含量为20.08、27.26g/kg时,与0.10 g/kg组相比显著降低(P<0.05),但与其他组相比差异不显著。因此研究认为:以生长指标为判据,不需要在饲料中补充钾,海水中钾和饲料原料中的钾能够维持皱纹盘鲍幼鲍的正常生长;但以生理指标(软体部粗蛋白质和钠含量,鳃Na+-K+ATP酶活力)评判,饲料中钾的适宜含量为2.12 g/kg。 相似文献
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K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles. 相似文献
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Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices 相似文献
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Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418 相似文献
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Summary According to light- and electron-microscopic observations the pineal organ of the 3-day-old chicken consists of a prominent end vesicle and a tapering parenchymal stalk. During this stage the pineal lumen is in open communication with the third ventricle. However, in the 40-day-old chicken, which still possesses a well-developed end vesicle, the proximal portion of the pineal stalk displays regressive changes leading to local fragmentation. At this stage the pineal stalk is reduced, and the pineal lumen is missing. In 1-year-old chickens the parenchyma of the proximal portion of the stalk is further diminished, and in 3-year-old domestic fowl is completely displaced by bundles of collagenous fibers, only some nerve fibers being present. This post-hatching pineal development may reflect the sequence of changes leading from pineal sense organs to pineal glands.This work was supported by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan 相似文献